Head on Resistivity Method Application in Geothermal Fields of El Salvador, Central America

Abstract

In order to identify mapped and hidden geological faults the Head On profile electric method has been applied in geothermal fields of El Salvador. In this country, there are two geothermal fields under production, in which many wells have been drilled, and also two fields in development and in all the fields the Head On resistivity method has been applied. Wells were directed to fractured zones suggested by the structural map and by alignments seen by the Head On method. The goal of this method is to identify the most fractured zones, making perpendicular profiles to the main direction of the faults system. Several alignments at the structural geologic map have been identified and others have been suggested by the method. The results have indicated that several zones have good permeability and could be intercepted with the drilling of successful wells. The fractures delineated with this method have been of great help to define the drilling targets in the geothermal exploration programme.